[PATCH v2 1/1] drm/i915/xehp: add wait on depth stall done bit handling

[Juha-Pekka Heikkila]

Add writing of WAIT_ON_DEPTH_STALL_DONE_DISABLE for gen12, this
is performance optimization.

Bspec: 46132

Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/12411
Signed-off-by: Juha-Pekka Heikkila <juhapekka.heikkila at gmail.com>
---
 drivers/gpu/drm/i915/gt/intel_gt_regs.h     | 3 +++
 drivers/gpu/drm/i915/gt/intel_workarounds.c | 6 ++++++
 2 files changed, 9 insertions(+)

diff --git a/drivers/gpu/drm/i915/gt/intel_gt_regs.h b/drivers/gpu/drm/i915/gt/intel_gt_regs.h
index 6dba65e54cdb..a6e50af44b46 100644
--- a/drivers/gpu/drm/i915/gt/intel_gt_regs.h
+++ b/drivers/gpu/drm/i915/gt/intel_gt_regs.h
@@ -409,6 +409,9 @@
 #define GEN7_SO_PRIM_STORAGE_NEEDED(n)		_MMIO(0x5240 + (n) * 8)
 #define GEN7_SO_PRIM_STORAGE_NEEDED_UDW(n)	_MMIO(0x5240 + (n) * 8 + 4)
 
+#define GEN8_WM_CHICKEN2			MCR_REG(0x5584)
+#define   WAIT_ON_DEPTH_STALL_DONE_DISABLE	REG_BIT(5)
+
 #define GEN9_WM_CHICKEN3			_MMIO(0x5588)
 #define   GEN9_FACTOR_IN_CLR_VAL_HIZ		(1 << 9)
 
diff --git a/drivers/gpu/drm/i915/gt/intel_workarounds.c b/drivers/gpu/drm/i915/gt/intel_workarounds.c
index db04c3ee02e2..116683ebe074 100644
--- a/drivers/gpu/drm/i915/gt/intel_workarounds.c
+++ b/drivers/gpu/drm/i915/gt/intel_workarounds.c
@@ -742,6 +742,12 @@ static void gen12_ctx_workarounds_init(struct intel_engine_cs *engine,
 		/* Wa_1606376872 */
 		wa_masked_en(wal, COMMON_SLICE_CHICKEN4, DISABLE_TDC_LOAD_BALANCING_CALC);
 	}
+
+	/*
+	 * This bit must be set to enable performance optimization for fast
+	 * clears.
+	 */
+	wa_mcr_write_or(wal, GEN8_WM_CHICKEN2, WAIT_ON_DEPTH_STALL_DONE_DISABLE);
 }
 
 static void dg1_ctx_workarounds_init(struct intel_engine_cs *engine,
-- 
2.45.2